package controller;

import com.fasterxml.jackson.databind.ObjectMapper;
import model.User;
import model.UserDao;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.PrintWriter;


@WebServlet("/login")
public class LoginServlet extends HttpServlet {

    private ObjectMapper objectMapper = new ObjectMapper();

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        req.setCharacterEncoding("utf8");
        resp.setCharacterEncoding("utf8");
        //1.获取请求中的参数
        String username = req.getParameter("username");
        String password = req.getParameter("password");

        System.out.println("username" + username +",password"+password);

        if (username == null || "".equals(username) || "".equals(password) || password == null){
            resp.setContentType("text/html;charset=utf8");
            resp.getWriter().write("当前用户名或密码为空");
            return;
        }
        //2.和数据库中的内容进行比较   --------------------------------需要修改---------------------
        UserDao userDao = new UserDao();
        User user = userDao.selectByName(username);


        if(user == null || !user.getPassword().equals(password)){
            //用户没有查到或密码不匹配
            resp.setContentType("text/html; charset=utf8");
            resp.getWriter().write("当前用户名或密码错误<br>");
            resp.getWriter().write(user.getUsername()+"  "+password);

            return;
        }

        //3.如果比较通过，就创建会话
        HttpSession session = req.getSession(true);
        //把刚才的用户信息存储到会话中
        session.setAttribute("user",user);

        //4.返回一个重定向报文，跳转到博客列表页
        resp.sendRedirect("blog_list.html");


    }


    //用来让前端检测当前的登录状态
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("application/json;charset=utf8");
        HttpSession session = req.getSession(false);

        //没有登录状态
        if(session == null){
            User user = new User();
            resp.getWriter().write(objectMapper.writeValueAsString(user));
            return;
        }

        User user = (User) session.getAttribute("user");
        if(user == null){
            user = new User();
            resp.getWriter().write(objectMapper.writeValueAsString(user));
            return;
        }


        //已经登录状态
        user.setPassword("");
        resp.getWriter().write(objectMapper.writeValueAsString(user));

    }
}
